CATS-ISS (Cloud-Aerosol Transport System for ISS) Science Overview

Transcription

1 CATS-ISS (Cloud-Aerosol Transport System for ISS) Science Overview Directed Opportunity Payload Delivery Date: April 2013 Planned Launch Readiness Date: mid-2013 CATS is a directed opportunity funded directly by NASA Science Operations Mission Directorate (SOMD). Total budget $10M (w/ contingency) Japanese Experiment Module-Exposed Facility (JEM-EF) attached payload for the International Space Station (ISS) Project initiated in April 2011, on 24 month rapid schedule to launch Pathfinder for future US Science payloads

2 CATS-ISS Organizational Chart Matthew McGill: CATS PI Judd Welton: Project Scientist S. Scott / 694 Instrument Manager CATS Project Science Team: Stephen Palm William Hart Dennis Hlvaka John Yorks M. McGill / PI/Project Manager J. Cavanaugh / 544 Instrument Systems Engineer S. Kunkel / GSFC 592 & JSC Project Interface Facilitator E. Welton / Science Definition Lead P. Colarco / Data Assimilation Modeling Support: Pete Colarco Arlindo da Silva Virginie Buchard M. Shupp / Resource Analyst W. Mamakos / D.I. Mechanical P. Adkins / 321 Payload Safety P. Cleveland / ESI Thermal S. Scott / 694 Optics JSC / ISS Safety & Mission Assurance J. Cavanaugh / 554 Electrical Fibertek Laser No Competed Science Team at the moment (ROSES NRA under discussion) N. Galassi / D.I. Structural Axsys Telescope Fibertek System Software

3 This image cannot currently be displayed. CATS-ISS Science Overview: Research & Operational Goals Near Real Time ISS CATS Processing Center NASA GSFC Operational Forecast Centers Aerosol and Cloud Properties GLAS Lidar Research AIR QUALITY MONITORING Forecasting STRATEGIC (DoD) Latitude MODIS Image Aerosol Modeling HAZARDOUS PLUME TRACKING

4 Climate Studies & Aerosol Forecasting Observations provide constraints needed to model aerosol properties and behavior Even with those constraints, modeling aerosol distribution and loading is difficult Aerosol climate impacts are proportional to loading! MODIS Aerosol Observations Modeled Aerosol Loading Zhang et al, 2008 Model aerosol loading improves significantly after assimilating coincident observations, but only for 2D total loading (as shown) Despite agreeing on total loading, current models diverge significantly on vertical distribution and aerosol type (ie pollution vs dust) As a result, it is difficult to attribute aerosol loading to human vs nature (ie pollution vs dust) Determining human induced portion of aerosol climate impact is the primary goal! Model Results after Assimilating MODIS Models are used to determine climate forcing and predict future climate change Aerosol climate forcing is dependent on vertical location: are aerosol below, mixed with, or above clouds? Aerosol Cloud interactions comprise the largest uncertainty in climate forcing

5 Climate Studies & Aerosol Forecasting Lidar provides: (1) information on the vertical profile of aerosol type, and properties (ie loading) similar information on clouds CALIPSO Observations (2) heights of aerosols and clouds, and improves our understanding of how and when aerosol cloud interactions occur CATS will provide data to constrain modeled aerosol and cloud properties, and improve model distributions and climate forcing through assimilation CALIPSO Feature Mask GEOS-5 Model Feature Mask Marine Aerosol Pollution Dust Pollution-Dust Smoke Welton, et al (2011)

6 ACE Mission Studies & Tech Demo ACE Mission Considering Different Mission Options: 1 or 2 Platforms ACE Mission still in study phase: If selected launch in 2020 s ACE Report Chapters 1 & 9: Introduction & Mission

7 Advanced Lidars: Particle Properties from High Spectral Resolution Lidar (HSRL) HSRL Total Signal, as measured by traditional backscatter lidars P T (r) C M (r) P (r) e 2 z 0 M ( r )d r e 2 P ( r )d r 0 z HSRL techniques provide additional channel containing only molecular backscatter P M (r) C M (r)e 2 z M ( r )d r 0 e 2 P ( r )d r 0 z and more accurate profiles of extinction can be solved directly if an accurate molecular model is used. Profiles of backscatter and the lidar ratio are also generated. 1. Use absorption notch filter to eliminate aerosol signal. Presence of Doppler shift will preclude measurement (e.g., off-nadir not easy). Or 2. Use Fabry-Perot etalon to image aerosol/molecular spectrum Doppler shift not a problem, but FP has low efficiency

8 Advanced Lidars: Exploring the Information Content & Simulating CATS GEOS 5 Inputs: Met Data Solar Stokes TOA (I,Q,U) Surface Albedo & Type Aerosol: BKS, EXT, Depol, SSA for sulfate, sea salt, dust, black & organic carbon Dust aerosols fully polarized No Clouds, yet

9 Advanced Lidars: Exploring the Information Content & Simulating CATS Sulfate BKS Seasalt BKS Dust BKS OC BKS BC BKS * 10

10 Advanced Lidars: Exploring the Information Content & Simulating CATS BKS 355 nm EXT 355 nm BKS 532 nm EXT 532 nm BKS 1064 nm EXT 1064 nm

11 Advanced Lidars: Exploring the Information Content & Simulating CATS BKS 355 nm DEPOL 355 nm BKS 532 nm DEPOL 532 nm BKS 1064 nm DEPOL 1064 nm

12 Advanced Lidars: Exploring the Information Content & Simulating CATS BKS 532 nm BKS 532/355 nm Ratio Lidar Ratio 532 nm BKS 1064/532 nm Ratio DEPOL 355/532 nm Ratio BKS 1064/355 nm Ratio

13 Parameters of Interest for Lidar Considering only parameters that are observed or retrieved directly

14 Lidar Capabilities ACE Lidar Requirements: 1064, 532, 355 nm backscatter lidar Depolarization at least 2, pref 3 HSRL Extinction & Lidar Ratio at 355, 532 nm This is so called lidar, with multiple depol. Considered minimum information content to retrieve microphysics. The color of data plot outline denotes wavelength: 355 nm 532 nm 1064 nm

15 Lidar Capabilities CALIPSO Capability: 1064, 532 nm backscatter lidar Depolarization at 532 nm No independent extinction or lidar ratio No multi wavelength depol Backscatter wavelength dependence (WV) is NOT used for aerosol typing

16 Lidar Capabilities EarthCare AT LID Capability: 355 nm Backscatter HSRL extinction & lidar ratio at 355 nm Depolarization at 355 nm No multi wavelength depol No wavelength dependence (WVD) Due to the wavelength difference, EarthCare cannot provide climate observation continuity with CALIPSO.

17 The ISS Cloud Aerosol Transport System (CATS) Lidar: Launch mid 2013 The Cloud Aerosol Transport System (CATS) is a lidar remote sensing instrument currently being developed for deployment to the International Space Station (ISS). The CATS lidar will provide range resolved profile measurements of atmospheric aerosol and cloud distributions and properties at three wavelengths (355, 532, and 1064 nm). Retrieved properties include: layer height and thickness, backscatter, optical depth, extinction, depolarization, and discrimination of aerosol type and cloud ice/water phase. CATS operates in one of six science modes to meet mission goals, utilizing various configurations of two high repetition rate lasers and four instantaneous field of view (IFOV). CATS Mission Goals: (A) Extend CALIPSO data record for continuity of Lidar Climate Observations Continue record of vertically resolved aerosol and cloud distributions and properties Improve our understanding of aerosol and cloud properties and interactions Improve model based estimates of climate forcing and predictions of future climate change (B) Improve Operational Aerosol Forecasting Programs Improve model performance through assimilation of near real time aerosol and cloud data Enhance air quality monitoring and prediction capabilities by providing vertical profiles of pollutants Improve strategic and hazard warning capabilities of events in near real time (dust storms, volcanic eruptions) (C) NASA Decadal Mission Pathfinder: Lidar for the Aerosols, Clouds, Ecosystems (ACE) Mission Demonstrate HSRL aerosol retrievals and 355 nm data for ACE mission development Laser Technology Demo/Risk Reduction: high repetition rate, injection seeding (HSRL), and wavelength tripling (355 nm) E.J. Welton, NASA GSFC Code 612, 2/13/2012

18 CATS Airborne Instrument CATS Instrument

19 CATS Science Modes CATS Science Mode 1 Capability: 1064, 532 nm backscatter lidar Depolarization at 532, 1064 nm No independent extinction or lidar ratio * Basic mode for goal (A) and (B), yet more capability than currently provided by CALIPSO ** Same capability as backup science modes 4,5,6

20 CATS Science Modes CATS Science Mode 4,5,6 Capability: 1064, 532 nm backscatter lidar Depolarization at 532, 1064 nm No independent extinction or lidar ratio * Basic mode for goal (A) and (B), yet more capability than currently provided by CALIPSO ** Same capability as science mode 1, but using laser 2 and different FOV selections

21 CATS Science Modes CATS Science Mode 2 Capability: 1064, 532 nm backscatter lidar 532 nm HSRL Depolarization at 1064 nm No multi wavelength depol * Mode 2 provides best capability for goals (A) and (B), and addresses HSRL objectives of goal (C) ** Caveat: HSRL retrievals from space are untested, this is primarily a tech and data demo mode. Objectives of Goal (B) include hindsight and model evaluation, not forecasting.

22 CATS Science Modes CATS Science Mode 3 Capability: 1064, 532, 355 nm backscatter lidar Depolarization at 1064, 532, 355 nm No independent extinction or lidar ratio Depolarization ratio 532/355 is desired for ACE Backscatter WVD now includes 3, should be better for fine mode aerosols * Mode 3 provides excellent capability for goals (A) and (B), and addresses 355 nm objectives of goal (C)

23 Pulse 2 CATS Observations: Raw Data At 5 Khz, each laser shot is separated by 60 km. 250 shots are summed onboard, then downlinked resulting in 350 m horizontal resolution along the ground track. 28 km Next Profile Data frame extent is fixed at 30 km Solar Background Constant In Each Bin Pulses Separated By 60 km Atmospheric Signal Profile (scattering from pulse as travels thru each bin) 30 m bins. Along Track Averaging.. Data frame top/bottom and resolutions shown here are nominal values for start of mission. Values may be changed via ground commands during the mission, with the following limitations: Data frame top/bottom values must equal 30 km extent, and allow sufficient sub surface data for solar background corrections Ellipsodial Surface ~ 350 m Pulse 1 2 km Solar Background Calculated Here (will contain some laser scattering from ~30 29 km) Surface Return (all laser photons scattered or absorbed at this time)

24 High Repetition Rate Side Effect: Simultaneous Pulse Signals (SPS) CATS Pulse Repetition Rate is 5 khz 58 km Pulse 2 at 65 km 1116 sfrom ISS (1316 sfrom Pulse 1 Start) Backscatter to CATS from both Pulses 1 (5km) and 2 (35 km) Pulses separated by 200 s, or 60 km SPS from successive pulse scattering in the stratosphere will be present in our lower 28 km data frame Most likely negligible during day, night time effect under study 28 km (Data Collection starts for pulse 1) Pulse 1 Backscatter Photons at 1416 s Backscatter to CATS Pulse 2 at 35 km 1216 sfrom ISS (1416 sfrom Pulse 1 Start) CATS calibration and data processing strategy will correct this issue Pulse 1 at 5 km 1316 sfrom ISS Backscatter to CATS 2 km Stratospheric SPS contribution to solar background calculation and atmospheric profiles will be modeled and characterized prior to launch Thick, attenuating clouds in upper troposphere and mountain overpasses (ie, Himalayan plateau) will offer conditions to characterize the stratospheric SPS during the mission

25 Simulated CATS Signals CALIPSO ABS 532 nm Lidar Ratio 532 nm BKS 532 nm BKS 532 nm DEPOL 532 nm CATS ABS 532 nm Lidar Ratio 532 nm

26 Simulated CATS Signals: 1 sec ave (~7 km along track), 30 m vertical ABS CoPol 355 nm ABS CoPol 532 nm ABS CoPol 1064 nm ABS CrossPol 355 nm ABS CrossPol 532 nm ABS CrossPol 1064 nm Total ABS 355 nm Total ABS 532 nm Total ABS 1064 nm

27 Simulated CATS Signals: 1 sec ave (~7 km along track), 30 m vertical Total ABS 355 nm Total ABS 532 nm Total ABS 1064 nm Vol Depol 355 nm Vol Depol 532 nm Vol Depol 1064 nm ABS 532/355 nm Ratio ABS 1064/532 nm Ratio ABS 1064/355 nm Ratio Vol DEPOL 355/532 Ratio Vol DEPOL 532/1064 Ratio Vol DEPOL 355/1064 Ratio

28 Simulated CATS Signals: 3 sec ave (~20 km along track), 30 m vertical Total ABS 355 nm Total ABS 532 nm Total ABS 1064 nm Vol Depol 355 nm Vol Depol 532 nm Vol Depol 1064 nm ABS 532/355 nm Ratio ABS 1064/532 nm Ratio ABS 1064/355 nm Ratio Vol DEPOL 355/532 Ratio Vol DEPOL 532/1064 Ratio Vol DEPOL 355/1064 Ratio

29 Simulated CATS Signals: 1 sec ave (~7 km along track), 30 m vertical Daytime

30 CATS Performance Simulation: Detection Limits Simulation prepared similar to CALIPSO approach. Attenuated Backscatter signal constructed at expected Level 0 downlinked resolution (350 m along track, 60 m vertical) Aerosol Layer simulated in first 10 segments (lidar ratio = 30 sr, weak sea salt layer) Cirrus Layer in segments (lidar ratio = 25 sr, typical for thin cirrus) 532 nm Results Shown Here, We are working on 355 and 1064 nm CATS Simulated Attenuated Backscatter: Night Detection algorithm applied to each layer and segment based on Yorks et al. (2011) and Palm et al. (2002) Detection improves as layer concentration/backscatter increases. Find optimum averaging to detect layer. * These results are preliminary, and operational algorithm will likely do better (as occurred with CALIPSO operational algorithm vs theoretical limits) Simulation Night Day 20 SZA Layer Backscatter Detection Thresholds (km -1 sr -1 ) 350 m 1 km 5 km 20 km 80 km km 1.33 E E E E E km 1.00 E E E E E km 1.33 E E E E E km 8.00 E E E E E-4

31 CATS ISS Orbital Coverage ISS Orbit: 51 inclination (not sun synch), altitude varies between km ~3 day near repeat cycle, ~60 day solar cycle overpasses File size (granule) planned at ½ orbit, processing frame size ~ 80 km (same as CALIPSO)

32 CATS ISS Orbital Coverage approx number of overpasses Local Time Coverage: January Hrs Local Time Hrs Local Time Hrs Local Time Local Time Coverage: February Hrs Local Time Hrs Local Time Hrs Local Time

33 CATS Data Comm & Processing System CATS Command/Control and Data Communications Command Control Commands initiated from CAPS Trek to POIC via VPN Ethernet POIC commands to ISS via TDRS Commands relayed to CATS via 1553 interface? CATS Raw Data Command ISS Science Data Raw data transmitted to ISS via HRDL ISS telemetry to POIC via TDRS POIC transmits data to CAPS Trek via VPN ethernet CAPS Trek transmits to CAPS Science via LAN (Final ISS raw data file processing at POIC) TDRS CAPS TREK Level 0 CAPS Science Archival & Processing POIC VPN Ethernet LAN NRT Capability is still unclear, but should be within 3 hours

34 Conclusion CATS has a 6 month operational requirement, and 3 year goal (with SOMD/ISS) Launch summer 2013 Launch Vehicle: JAXA HTV CATS instrument is on track and moving along well toward delivery Passed PDR last year, and CDR earlier this year Algorithm development has begun, using GEOS 5 as simulation base Performance studies are underway for each channel in each science mode Currently working with NASA HQ to secure multi year funding for CATS Science team, algorithm development, and operations Includes collaboration with LaRC/CALIPSO team to address continuity studies between CALIPSO & CATS (ie, develop methods to run CATS data thru CALIPSO processing) CATS data will follow CALIPSO file conventions to ease strain Other CATS data format for operational use is open for discussion Algorithm peer review(s) are planned, ~ early 2013 CATS ROSES NRA has been discussed with HQ, if a go then summer 2013 release Looking for feedback from ICAP community on NRT data for operational support!